Merge tag 'media/v5.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab...

[sfrench/cifs-2.6.git] / drivers / staging / media / ipu3 / include / intel-ipu3.h

diff --git a/drivers/staging/media/ipu3/include/intel-ipu3.h b/drivers/staging/media/ipu3/include/intel-ipu3.h
index c7cd27efac8af68d702b3d25479c89ddb3e672f7..08eaa0bad0de66405f3b716f239a9fdb107d39ea 100644 (file)
--- a/drivers/staging/media/ipu3/include/intel-ipu3.h
+++ b/drivers/staging/media/ipu3/include/intel-ipu3.h
@@ -1217,6 +1217,11 @@ struct ipu3_uapi_shd_config {
  *
  * All CU inputs are unsigned, they will be converted to signed when written
  * to register, i.e. a01 will be written to 9 bit register in s4.4 format.
+ * The data precision s4.4 means 4 bits for integer parts and 4 bits for the
+ * fractional part, the first bit indicates positive or negative value.
+ * For userspace software (commonly the imaging library), the computation for
+ * the CU slope values should be based on the slope resolution 1/16 (binary
+ * 0.0001 - the minimal interval value), the slope value range is [-256, +255].
  * This applies to &ipu3_uapi_iefd_cux6_ed, &ipu3_uapi_iefd_cux2_1,
  * &ipu3_uapi_iefd_cux2_1, &ipu3_uapi_iefd_cux4 and &ipu3_uapi_iefd_cux6_rad.
  */